A CaZrO3-based compound has been widely used for temperature-compensating capacitors because it has a small temperature coefficient of electrostatic capacitance and a small dielectric loss, i.e., small tan δ.
In general, this type of multilayer ceramic capacitor is manufactured by the steps of laminating ceramic green sheets provided with conductive patterns thereon to form a ceramic laminate, performing a firing treatment for this ceramic laminate to form a ceramic base body having internal electrodes embedded therein, then applying a conductive paste on two end portions of the ceramic base body, performing a baking treatment to form external electrodes, and forming plating films of Ni, Sn, and the like on the surfaces of the external electrodes.
In addition, a multilayer ceramic capacitor has been proposed heretofore (in Patent Document 1) having a structure in which the ceramic layer (ceramic base body) is composed of a ceramic material containing a composite oxide represented by (CaO)x(Zr1−y. Tiy)O2, 1.0 to 3.0 parts by weight of an Mn compound in the form of MnCO3 and 0.5 to 2.0 parts by weight of a Li2O—B2O3—CaO-based glass component, each amount being relative to 100 parts by weight of the composite oxide, and in which internal electrodes are formed from a Cu-based conductive material.
According to this Patent Document 1, besides the CaZrO3-based composite oxide used as a primary component, the ceramic layer contains the Mn compound and the Li2O—B2O3—CaO-based glass component as auxiliary components, and in addition, the internal electrodes are formed from inexpensive Cu having superior electrical conductivity; hence, a low-temperature firable multilayer ceramic capacitor can be obtained in which the temperature coefficient of electrostatic capacitance satisfies the CG characteristic (within ±30 ppm/° C. relative to an electrostatic capacitance at 25° C. in a temperature range of −55 to 125° C.), and in which a high Q value (=1/tan δ), such as 10,000 or more, and a relative dielectric constant of 28 to 32 are achieved.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 11-283860